Plantar fasciitis, a repetitive strain injury, is one of the most common causes of foot pain. Ten percent of aging
adults experience plantar fasciitis with 50% of the cases being disabling. Foot pain can lead to other problems
such as reduced mobility, depression and prescription medication use, leading to a reduced quality of life.
Relationships have been established between foot pain and weakness, reduced static and dynamic balance,
and reduced walking speed in aging adults. The standard of care for plantar fasciitis is to brace the foot with
foot orthoses and supportive shoes. However, chronic support of the arch has been shown to lead to intrinsic
foot muscle atrophy. As plantar fasciitis is associated with this atrophy, treating it with chronic arch support
only increases the risk for recurrence. In fact, there is a 50% recurrence rate and a 45.6% risk of having
plantar fasciitis 10 years after the onset of symptoms in older adults.
Minimal shoes are designed to allow the foot to function naturally, as if barefoot. They have already been
successfully implemented in older adults for the treatment of knee osteoarthritis. Minimal shoes are highly
flexible and lack the support of conventional footwear. This places greater demand on the foot muscles which
promotes strengthening. Stronger foot intrinsic foot muscles have been shown to reduce the strain on the
plantar fascia with each step, thereby reducing the risk of developing plantar fasciitis.
Long-term Goal: To improve treatment interventions for plantar fasciitis in aging adults.
Specific Aims: 1. Compare pain and physical function between the minimal footwear (MF) and the foot orthotic
(FO) groups at the 3 and 6 month follow-up, 2. Compare changes in intrinsic foot muscle size and strength
between MF and FO groups at the 3 and 6 month follow-up, and 3. Compare the incidence of recurrence of
plantar fascial pain between the MF and FO groups at the 12 month follow-up
Methods: 120 participants with plantar fasciitis (>6 mos.) will be recruited from 2 sites. They will be
randomized into a minimal footwear (MF) and foot orthotic (FO) group. Baseline measures of foot muscle size
and strength, static and dynamic balance, 6 min. walk test and two functional outcome questionnaires will be
obtained. The MF group will receive 2 pair of minimal shoes, and the FO group will receive 2 pair of supportive
shoes and prefabricated foot orthoses. The MF group will be given a 4-week program of foot strengthening
and flexibility exercises, while the FO group will only receive the flexibility exercises. Both groups will be given
an 8-week footwear transition program based upon their individual baseline step counts. They will return to the
laboratory to repeat the baseline measures at 3 and 6 mos. Plantar fascial pain and daily step counts will be
monitored over the course of the year. Comparisons in outcome measures as well as plantar fasciitis
recurrence will be compared between the groups.